It’s hard to say at the moment the only gasket breach I found was here in this pic around the top of the cylinder. I still need to take off the timing chain cover and see what that looks like. Other than that the head gaskets looked good on all the coolant passages.Have you identified the cause of the problem?
This motor was rebuilt about 10 yrs ago, and yes there was coolant in the pan when drained. It was run for awhile before it was discovered unfortunately.Looks like coolant got into the oil pan, then it was ran awhile. Any overheating issues? How long has it been running bad? Take it all apart, and start again. Was it re built recently?
What I can’t figure is why that upper chunk would allow any coolant through because it’s not even connected to a passageI’d tear it all down...... every thing in there needs a thorough cleaning and lubing.
For some reason, I thought it was a big block.
I’d say that missing chunk of head gasket connected to that coolant hole is the source of the problem.
The timing chain cover is actually my guess as to why this happened but I will need to get it off to check it out. Haven’t gotten the crank bolt off yet, I sprayed some penetrating oil to help me out the next time I go back to it cuz I could not budge it earlier.Check the timing chain cover. They corrode and can send water into the oil. All the parts may be fine but it's worth a look at the bearings and a good cleaning to be safe. On the other side of the coin I saw plenty of motors at the Dealer that got a head gasket and a oil change and went on their merry way. In the words of Clint Eastwood "you got to ask yourself. Do I feel lucky?"
Doug
That’s a good observation! Although they all have reliefs and it’s just not very visible in the pic. Here are those cylinders.Might I ask why the forward 2 pistons look like flat top pistons while the other 2 have valve reliefs?
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